From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Synchromesh mechanism failure, gear lever modification, and notes on rear hubs and brakes.
| Identifier | ExFiles\Box 182\M18\ img058 | |
| Date | 12th April 1941 guessed | |
| -6- clutching effect is to substantiate our remarks upon the revolving mass. At an approx. mileage of 2970, we had a temporary failure of the synchromesh mechanism whilst changing from 3rd to top. The driver was making a quick change at a speed between 40 - 50 m.p.h. upon reaching the brow of a hill. The change speed lever moved almost to its normal position but went no further. The car came to rest, the synchromesh mechanism having seized. The top gears were just upon the point of engagement. The cover of the gearbox was taken off. It was found that the cones could be moved freely but not the sleeve coupled up to the lever. Nothing could be done on the road to ascertain the failure, therefore after allowing a few minutes for the parts to cool down, the gear lever was jossled about and the neutral position was obtained. The 3rd gear was engaged quite normally, therefore the car resumed its journey with a view of returning to the garage, but upon trying the top gear again it functioned quite normally and no further sign of seizing reappeared. We again examined it upon its return but could not make it fail, or see why it had failed, without taking the whole gearbox down. We assumed the temporary failure was caused either by the plungers sticking or a slight picking up of metal on the shaft serrations. We have repeatedly tried to make it fail again, but so far have not succeeded. - series of gear changing has been carried out through the mileage, i.e. 40 changes from top to 3rd, and 40 changes from 3rd to top, running approx a quarter of a mile on 3rd gear in each case. One mile on the 1st gear and 2nd gear respectively has also been run during each 250 miles. CHANGE GEAR LEVER PLUNGER to Arrgt. EX.8727 DELETING FRONT OPERATED PLUNGER. This was suggested and fitted to delete the small area of the plunger, leaving the top of the change speed lever smooth and more agreeable to handle. We have appreciated the smooth top during the many gear changes made and in no way has it affected the operation of the reverse. REAR HUBS to LOP.1.77235. H.S.3177. G.79502 Brakes Drums RR. Castings similar to Lake & Elliott's specification. H.7120 Bolts - replacing studs for fixing End Plates. Stronger auxiliary Brake Shoe Springs G.80050 fitted. The rear brakes have been very efficient, smooth and free from groans. The brake drums when examined at a mileage | ||